1. Field of the Invention
The present patent application for industrial invention relates to an improved plow.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
Plows have been used in agriculture since the earliest times to move the soil and prepare it for additional works or directly for sowing.
Historically speaking, the plow is a sort of evolution of the pick. In the past it was pulled by oxen or people. Today, in modernized countries, it is pulled by mechanical tractors.
Traction is mechanical in countries with mechanized agriculture, and plows are mounted on tractors and fixed to a hauling hook, resting on wheels (so-called hauled plows). Alternatively, being always hauled by the tractor, plows are fixed to a hydraulic power lift (so-called carried plows that project from the tractor without the support of wheels). Carried plows are mostly used in ordinary work because they make road transfers easier.
The current models of plows can be grouped in different categories according to the type of system used for attachment to the motor vehicle (hauled plows, semi-carried plows and carried plows), the type of tool (fixed single or multiple tool and idle tool) and the type of adjustment and control system of the working parts (tools) installed on each type of plow.
All types of plow are provided with some common parts that can be divided into three categories according to their function: working tools, such as coulter (or knife), chisel, share and moldboard; connection, support and guide devices, such as beam, horizontal bar; and adjustment devices to control the burying and filling operations of the working tools and adjust the working depth and width.
FIG. 1 shows a traditional plow according to the prior art, which is generally indicated with reference number (100), mounted on a motor vehicle, specifically a tractor in FIG. 1, indicated with reference number (200).
FIG. 2 is an enlarged view of the traditional plow according to the prior art shown in FIG. 1.
The plow (100) according to the prior art comprises:                a share (6) used to cut the soil,        a moldboard (7) connected to the share (6) used to turn over the clods of soil cut by the share,        a beam (1) connecting the share-moldboard assembly to a motor vehicle (200).        
On the whole, the beam (1) supports the entire ploughing effort exerted through the various tools used to work the soil (6) are the most worn-out parts.
The plow (100) is completed by adjustment devices (3) that control the burying and digging operations of the beam together with all working tools, and adjust the depth and width of the furrows.
In spite of being a diffused practice, ploughing is impaired by several drawbacks.
Ploughing with a plow of the prior art is a very expensive operation in terms of energy, with consequent high fuel consumption for the motor vehicle. Moreover, ploughing according to the prior art leaves macro clods on the surface of the soil because of the poor definition of the furrow made in the soil by the working parts of the plow as consequence of the cuts. Therefore, it is often necessary to carry out preparation works of the seed bed, thus extending the time needed for sowing, making it difficult to rotate crops, involving higher fuel costs and worsening the structure of the soil due to the repeated travels of the plow.
The use of a vibrator applied to the plow is known in order to solve, at least partially, the aforementioned drawbacks.
The use of vibrators with connecting rod-crank system with predefined travel is known.
EP1108349 discloses actuating means comprising an eccentric-connecting rod transmission connected to the frame (beam) of the plow. The connecting rod is connected to the blade of the plow by means of rods. The blade is mounted in a grooved guide of the moldboard in such manner to slide. In this way, the blade of the moldboard makes an alternate movement with about 7-8 mm travel with frequency (vibrations) in the range of 500-1200 per minute. The blade of the moldboard is connected to the frame of the plow by means of the connecting rod and levers. Consequently the travel of the blade is fixed and cannot be adjusted during ploughing.
DE1557822 discloses a vibrator comprising a statically balanced eccentric disk, instead of an eccentric mass that transmits vibrations. As a matter of fact, said vibrator transmits oscillations just like a crank (eccentric) and a connecting rod. The size of the oscillations depends on the double of the eccentricity value of the eccentric, which guarantees the oscillation around the fulcrum of the mobile system.
Consequently, the type of plow disclosed in EP1108349 and DE1557822 may be subject to jamming in case of obstacles, such as stones or harder materials.
Vibrators with eccentric masses are known to solve these drawbacks at least partially.
DE2604415 discloses a vibrator disposed on a support in the proximity of the share of the plow and elastic means to dampen the vibration and prevent it from propagating to the frame of the tractor.
GB519046 discloses a moldboard connected to the frame of the plow with resilient means (elastic supports). An eccentric shaft is directly connected to the structure of the moldboard. The eccentric shaft is actuated by a pulley driven by a belt in such manner to put the moldboard in high-frequency vibration. The eccentric shaft can be actuated by an electric motor or by the tractor and can provide vibrations in the ultrasound range.
Although they do not have a fixed travel, the vibrators with eccentric masses disclosed in DE2604415 and GB519046 are impaired by the fact that they work at a predefined excitation force that cannot be varied during the operation of the plow according to the type of worked soil.
The purpose of the present invention is to eliminate the drawbacks of the prior art and, particularly, reduce fuel costs, being ploughing one of the most energy-consuming activities.
Another purpose of the present invention is to obtain a better crumbling of clods, as well as better defined furrows, thus making it easier to prepare the seed bed.